Growth curve parameters of lines of Japanese quail (Coturnix coturnix japonica), unselected and selected for four-week body weight

This study was carried out to estimate growth curves of control and selection lines which was selected for higher 4-week body weight for five generations and to compare three nonlinear growth models (Gompertz, Bertalanffy and Logistic) in terms of fitting to quail data, and identify genetic and environmental effects on growth curve parameters. Body weights from hatch to sexual maturity were measured twice a week to study growth pattern of quail. Gompertz, Bertalanffy and Logistic models provide a better description of growth curve of quail summarizing age-weight data into the three growth curve parameters. Although all growth models used fit the quail data well, Gompertz was the best model. Line and sex were generally significant effects on growth curve parameters. Genetic variation in asymptotic weight were observed. The high correlation among the same growth curve parameters (say A) from different models show that the parameters tend to measure similar characteristics of growth.